AMV is a video file format, produced for use in Chinese MP3/MP4/MTV Players; classified as S1 MP3 Players. Note that despite the word "MP4" in the description of several players, this is not an MP4 file format. Video is the technology of electronically capturing, recording, processing, storing, transmitting, and reconstructing a sequence of still images which represent scenes in motion. ... File has several meanings: Computer file File (tool) file (Unix), a program used to determine file types. ... Format has several meanings; did you mean: Disk formatting — the process of preparing a disk for use File format — various ways information is encoded in computing Format — a command in the Common Lisp programming language Radio format — the musical style and programming philosophy of a radio... MP4 Player Chinese MP4/MTV Player is a flash based MP3 player, mostly manufactured in China, capable of viewing images, videos, and text files. ... An unbranded flash-based S1 MP3 Player S1 MP3 Players are a type of Chinese-made digital audio player. ... MP4 can refer to: MPEG-4 Part 14 file format Møller-Plesset perturbation theory of the fourth order This is a disambiguation page — a navigational aid which lists pages that might otherwise share the same title. ...

Video compression ratio is low, compared with other formats, though as the files are of low resolution and frame rate, file sizes are small compared to DVD/VCD/etc. (in a bytes-per-minute sense). Encoding and decoding are less processor-intensive than other contemporary formats (i.e. faster to encode on, say, desktop computer, and less hard on the batteries of the portable device), as in fact very little "encoding" is actually done.

For example (using typical values/approximations):

(note: AMV calculations based on 30 minutes at 128 x 96 pixels, 12 frame/s, 22050 sample/s mono sound : 80 MB (approx) The audio is 22050 sample/s, mono, MP3(?) - a safe guess would be a maximum of 10 MB being audio, yielding 70 MB for video, or approximately 40,000 bytes per second.)

Software available (to date April 2nd 2006) currently give screen sizes of 94x64, 128x96 and 128x128, typically set to frame rates of 8, 12 and 16 frames per second (described as "low","medium" and "high"), which fits reasonably well on 1.2 to 1.5+ inch screens. By editing configuration files the range of frame rates handled by the encoder can be expanded to 8-24 (in 1fps increments), though using alternate framerates may cause problems if the player is not designed for those alternates.

• AMV encoding tips
• How to convert to .AMV from www.MyMPxPlayer.org

There is also currently available a utility that will allow conversion between various other formats to AMV with screen settings, picture and audio quality. Other selections include the ability to 'zoom', (MODE in the programmers design terms). At present, there does not seem to be a utility that will convert AMV to any other format.